Econ 219B
Psychology and Economics: Applications
(Lecture 1)
Stefano DellaVigna
January 22, 2013
Outline
1. Introduction / Prerequisites
2. Getting started!Psychology and Economics: The Topics
3. Psychology and Economics: Empirical Methods
4. Methodology: Reading the Psychology Journals
5. Psychology and Economics by Field
6. Defaults and Retirement Savings: The Facts
1 Who am I?
Stefano DellaVigna (call me Stefano)
• Professor, Department of Economics
• Bocconi (Italy) undergraduate (Econ.), Harvard PhD (Econ.)
• Psych and Econ, Applied Microeconomics, Media Economics, PoliticalEconomy, Behavioral Finance,
• Evans 515 — OH schedule by email
2 Who are you?
• PhD student 2nd year and higher. Graduate courses in
— Econometrics
— Micro Theory
— Psychology and Economics — Theory (219A)
• Interest in
— Psychology and Economics
— Applied, empirical microeconomics (io, labor, public finance, finance)
3 What is this class?
• Reading list:
— complete, updated list on course webpage
— ‘Textbook’: “Psychology and Economics: Evidence from the Field”(Journal of Economic Literature 2009)
— 11 Methodological Topics
— Please email me ([email protected]) for any issue with classand to schedule a meeting
• Grade:
— 3 or 4 problem sets on models and empirics (30% weight)
— Final exam (40% weight)
— Your choice of:
∗ 10-15 page paper that uses field evidence (30% weight)
∗ An empirical problem set (30% weight)
• I encourage you to try to write a paper
• Deadlines for paper
— Meet with me about your paper by 3/2
— Brief summary of your research idea by 4/6 (2 pages, research question,data availability)
— Paper due on 5/10
• Information Sheet
4 Psychology and Economics: The Topics
• Prototypical economist conception of human behavior(Rabin, 2002a):
max∈
∞X=0
X∈
()³|
´
• is set of “life-time strategies”, is set of state spaces
• () are rational beliefs, ∈ (0 1) is time-consistent discount factor
• (· ) is true utility at time in state
• Improving Psychological Realism
• Step 1. Non-Standard Preferences
1. Present-Biased Preferences: time inconsistency ( )
2. Reference Dependence: (| ) with reference point
3. Social Preferences: ( −|) where − is allocation of others
• Example 1. Reference Dependence — Sydnor (AEJ: Applied, forthcoming)
• Sydnor studies deductible choice in home insurance policies
• Menu: $250, $500, $1,000. Higher deductible — Lower premium
• Example 1. Reference Dependence — Sydnor (AEJ: Applied, forthcoming)
• Sydnor studies deductible choice in home insurance policies
• Menu: $250, $500, $1,000. Higher deductible — Lower premium
• Example 2. Social Preferences — Gneezy and List (EMA, 2006)
• Recruit workers to enter manually data on books for 6 hours for $12/hour
• Treatment (gift) group: After hiring, told pay increased to $20/hour
• Example 2. Social Preferences — Gneezy and List (EMA, 2006)
• Recruit workers to enter manually data on books for 6 hours for $12/hour
• Treatment (gift) group: After hiring, told pay increased to $20/hour
• Step 2. Non-Standard Beliefs: beliefs () 6= ()
1. Overconfidence: wrong () or wrong ()
2. Law of Small Numbers: Wrong forecast of (+1|)
3. Projection Bias: wrong forecast of utility: (· )
• Example 3 — Conlin, O’Donoghue and Vogelsang (AER, 2007)
• Examine mail orders of cold-weather apparel
• Relate temperature on order date to return probability
• Standard model: No relation or positive relation (the colder it is now, themore you will need it in 5 days)
• Example 3 — Conlin, O’Donoghue and Vogelsang (AER, 2007)
• Examine mail orders of cold-weather apparel
• Relate temperature on order date to return probability
• Standard model: No relation or positive relation (the colder it is now, themore you will need it in 5 days)
• Correlation consistent with projection bias
• Current state 0 future state Predicted future utility ( ) = (1− ) ( ) +
³ 0
´
• Structural estimation of projection bias parameter
• Correlation consistent with projection bias
• Current state 0 future state Predicted future utility ( ) = (1− ) ( ) +
³ 0
´
• Structural estimation of projection bias parameter
• Step 3. Non-Standard Decision-Making
1. Limited Attention: maximization set 6= (neglect less salient alterna-tives)
2. Menu Effects: Do not max
3. Persuasion and Social Pressure
4. Emotions
• Example 4. Limited Attention — Huberman and Regev (JF 2002)
• November 28, 1997: EntreMed company (biotech) discovers cure for can-cer — Articles on Science, Nature, NYT (page 23)
• May 3, 1998: NYT repeats article on page 1
• Example 5. Menu Effects — Iyengar, Huberman, and Lepper (2006)
• Data set on choice of 401(k) plans
• Comparison of plans with few options and plans with many options
• Focus on participation rate — Fractions of employees that invest
• Step 4. Market Response to Biases
• Integrate these findings into a market
1. Firms (Behavioral IO)
2. Employers (Behavioral Labor)
3. Investors (Behavioral Finance)
4. Managers (Behavioral Corporate Finance)
5. Politicians (Behavioral Political Economy)
6. ...
• Example 6 — DellaVigna and Malmendier (QJE, 2004) (applied theorypaper)
• Credit card customers are:
— tempted to over-consume (self-control problems)
— naive about self-control problems
• How should credit-card companies price cards?
• Offer no yearly fee + bonuses (cash back, airline miles)...
• ...AND charge high interest rates
5 Psychology and Economics: Empirical Meth-
ods
• Psychology and Economics is
— Idea from Psychology (Self-control, Reference Dependence, Overconfi-dence, Inattention, Social Preferences, Persuasion,...)
— Setting in Economics (Asset Pricing, Charitable Giving, Consumptionand Savings, Job search, ...)
• Each setting has specific methodologies — Variety of methodologies
• Defining feature for the field is idea, not technique or methodology
• However: Five main methodologies in Field P&E
1. Menu choice
(a) Example 1. Sydnor (forthcoming) on small-scale risk aversion
(b) Compare behavior in a menu (Ex.: deductibles)
(c) Given a model, make inferences about preferences, beliefs, etc. (Ex.:Risk aversion)
2. Natural Experiments
(a) Example 4. Huberman and Regev (JF, 2002) on limited attention
(b) Treatment vs. Control comparison
(c) Quasi-random Naturally occurring events(Ex.: timing of article publi-cation)
3. Field experiment
(a) Example 2. Gneezy and List (EMA, 2006) on gift exchange
(b) Treatment vs. Control comparison
(c) Explicit randomization in a field setting (Ex.: Additional pay)
4. Correlational studies
(a) Example 5. Iyengar, Huberman, and Lepper (2006) on choice overload
(b) Test correlation of two variables (Ex.: No. options and participation)
(c) Derive conclusion — Correlation, not causality here
5. Structural Identification
(a) Example 3. Conlin, O’Donoghue and Vogelsang (AER, 2007) on pro-jection bias
(b) Write out model
(c) Estimate the parameters of the model (Ex.: projection bias)
6 Methodology: Reading Psychology Journals
• One strategy for papers in Psychology and Economics:
— Get idea from reading psychology literature
— Think of economic setting to apply to
∗ Model new phenomenon
∗ Test with economic experiments
∗ Apply using field data
• How to start with psychology literature?
• Step 1. Choosing your Psychology. Not all kinds of psychology are equallyuseful!
— Social Psychology (attribution errors, emotions, discrimination). YES!
— Cognitive Psychology (Kahneman and Tversky agenda). YES!
— Personality Psychology (Big Four personality types). Not very opti-mistic (Michigan and NYU group more optimistic)
— Developmental Psychology (Development of skills in children). Notmuch so far, may become important (see Bill Harbaugh’s experiments)
— Comparative Psychology (Example: Asians not overconfident). Diffi-cult to test empirically, but promising
• Step 2. Where to start?
— Read a good introductory book
∗ On social psychology I strongly recommend L. Ross and R.E. Nisbett,The Person and the Situation, McGraw-Hill, 1991-2011.
∗ On cognitive psychology a classic is Daniel Kahneman, Paul Slovic,and Amos Tversky. Judgment Under Uncertainty: Heuristics andBiases, Cambridge University Press, 1982
— Attend a graduate (or undergraduate) class in social of cognitive psy-chology. Check listing in Psychology, Sociology (Robb Willer), GSPP(Jack Glazer), and Haas (OB/Marketing)
• Step 3. Continuing education — Choosing the psychology journals
— Look for the top psychology journals:
1. Journal of Personality and Social Psychology (JPSP)
∗ Mostly very high-quality experiments
∗ Go directly to design–Do not stop at summary
∗ Skip the Section on personality psychology
2. Psychological Science
∗ Recent journal, exteremely successful
∗ Publishes short articles, like Science
3. Psychological Bulletin
∗ Publishes mostly reviews
4. Psychological Review
∗ Publishes ‘theoretical’ contributions, i.e., attempts to summarizeexisting experimental evidence. No Greek letters!
— Top marketing journals can be useful too
1. Journal of Consumer Research. Generally the most psychology-based
2. Also Journal of Marketing Research
• Step 4. Reading a psychology article
— Do not go for the newest finding.
∗ Look for findings that have been replicated, preferably by differentresearchers
∗ Use Google Scholar for that
— Reading group: Reading the articles in a group of 2-3
— Psych articles will contain typically 3-6 experiments. Focus on strongestone or two
— Classical issues to look for:
∗ Sample sizes small
∗ Are outcome variables interesting?
∗ Deception
— Psych authors tend to claim that they found a new effect — Look forunifying theme instead
— Read meta-analyses (summaries of experiments in an area) – But bewary that many bad experiments do not make a good one
• Step 5. Apply it to economics
1. Criticize the findings
— Are they relevant for economics?
— Can existing economic models explain it? (information stories oftensuccessful)
2. Find economic problem could apply to
— Brainstorm: charitable giving, yes-men in companies, shopping be-havior,...
3. Look for related papers in economics (and psychology)
• It may not work, but you will learn much
7 Psychology and Economics by Field
1. Public Finance
(a) Present-bias (addiction, sin taxes, retirement savings)
(b) Social preferences (charitable contributions)
(c) Limited attention (incidence of taxes, low take-up of benefits)
2. Environmental Economics
(a) Reference dependence (WTA/WTP)
(b) Framing effects (value of a life)
3. Labor Economics
(a) Reference dependence (labor supply, wage setting)
(b) Social preferences (wage setting)
(c) Money Illusion (wage setting)
4. Development Economics
(a) Present-bias (commitment devices in savings, choice of crops)
(b) Social preferences (group savings, trust, ethnic hatred)
5. Industrial organization
(a) Present-bias (Credit cards)
(b) Reference dependence (sales)
(c) Demand estimation + Profit maximization
6. Marketing
(a) Menu effects (Strategic pricing of products)
(b) Present-bias (Placement of tempting products)
7. Law and Economics
(a) Present-bias (Cooling off period)
(b) Emotions (litigation)
8. Political Economy
(a) Market Reaction (manipulation of hatred or inattention)
(b) Welfare Enhancement (SMRT plan)
9. Asset pricing
(a) Overconfidence (overtrading)
(b) Heterogeneity and Market Reaction (noise traders)
(c) Limited attention (footnotes in accounting, demographics, large events)
10. Corporate finance
(a) Overconfidence (investment, mergers, options)
(b) Limited attention (media)
11. Macro — Consumption/Savings
(a) Present-bias (low saving + mostly illiquid wealth)
(b) Reference dependence (nominal wage rigidity)
(c) Limited attention (menu costs)
8 Defaults and 401(k)s: The Facts
• 401(k) savings most common voluntary savings vehicle in the US
— Set aside money for retirement
— Choice of percent contribution, and stocks/bonds composition
— Penalty for early withdrawal
— Sometimes: Company matching of contribution up to a threshold
• Patterns of 401(k) investment (Highly recommended survey: Choi et al.,2006 — “Saving for Retirement on the Path of Least Resistance”)
• Today: Focus on Default Effects
• Fact 1. Close to 50% of investors follows Default Plan (at leastinitially)
• Madrian and Shea (QJE, 2001): Single most important piece of field evi-dence on P&E
• Details:
— Health Care company
— Paper-and-pencil 401(k) choice
— Can enroll any day
• Design (Table 1)
— Discontinuity of 401(k) plan defaults depending on date of hire
— After 4/1/1998 investment by default
— 50 percent match up to 6% contribution
— Observe effect on investment decisions
• OLD Cohort hired 4/1/96-3/31/97:
— default: no enrollment
— 1-year wait period for eligibility
• WINDOW Cohort hired 4/1/97-3/31/98:
— default: no enrollment
— wait period for eligibility till 4/1/98
• NEW Cohort hired 4/1/98-3/31/99:
— default: enrollment in 3 percent money market fund
— immediate eligibility
• Step 1. Check Design (endogeneity issues)
— Compare different cohorts: No large differences
• Step 2. Compare plan choices:
1. Participation rates in 401(k) by June 30, 1999 (Figure I and Table IV):
• OLD: 57%, WINDOW: 49%, NEW: 86%
1. Contribution rates (Figures IIc):
• WINDOW: 63% are at 0 percent, 4% at 3 percent
• NEW: 65% are at 3 percent (Default)
1. Allocation of funds in stocks (Figure III):
• OLD: 75%, WINDOW: 73%, NEW: 16%
• Results equally strong with controls (Table VI)
• Results very robust. Choi et al. (2004) Survey paper:
• Company B switches from OLD to NEW to OLD
• Company C switches from OLD to NEW to NEW2
• Company D switches from OLD to NEW to NEW2
• Company H switches from OLD to NEW
• Summary.
— OLD and NEW cohorts invest very differently one year after initial hire
∗ Fact 1. Fact 1. 40% to 50% of investors follow Default Plan
∗ Fact 1a. Applies to participation (yes/no)
∗ Fact 1b. Applies also to contribution level and allocation
— (Less commonly cited) WINDOW cohort resembles OLD cohort
∗ Fact 2. ‘Suggested choice’ not very attractive unless default
• BUT: Default effects not informative of optimal saving plans.
— Is OLD cohort under-saving?
— Or is NEW cohort over-saving?
• Introduction of Active Choice (Carroll et al., 2009) — Large Fortune-500Company, Financial sector
• Comparison between Active Choice (before) and No Enrollment (after)
• Fact 3. Active Choice resembles Default Investment
• ACTIVE Cohort, hired 1/1/97-7/31/97
— 30 days to return 401(k) form with legal packet
— Next enrollment period: January 1998
— Paper-and-pencil form
• OLD2 Cohort, hired 1/1/98-7/31/98
— Standard, no-saving-default (like OLD)
— Can enroll any time
— Telephone-based enrollment, 24/7
• Step 1. Check Design
— Summary Stats (Table 2)—No substantial difference across cohorts
• Step 2. Compare plan choices (Figures 1 and 2)
— Participation rates in 401(k) using cross-sectional data (Figure 1):
∗ ACTIVE: 69% — OLD2: 41% (at month 3)
∗ Compare to NEW (86%) and OLD (57%) in MS01 after 6 months
∗ Does not depend on month of hire (see below)
• — Contribution rates (including zeros) (Figure 3)
∗ ACTIVE: 4.8% — OLD2: 3.5% (at month 9, when longitudinal datebecomes available)
• — Contribution rates (excluding zeros) (Figure 4)
∗ ACTIVE: 6.8% — OLD2: 7.5% (at month 9)
∗ Selection effect: Marginal individuals are lower savers
• — Differences between ACTIVE and OLD2 disappear by year 3 (Figure 2)
— Still: Important because no catch-up in levels, and because of frequentchanges in employers
• Summary.
— ACTIVE is close to NEW and differs from OLD and OLD2
∗ Fact 3. Active Choice resembles Default Investment
∗ Fact 3b. Month of Hire does not matter
— Fact 4. Effect of default mostly disappears after three years
• Prevalence of OLD Default can (at least in part) explain under-saving forretirement
• Other evidence on default effects in choice of savings: Cronqvist and Thaler(2004, AER P&P)
— Privatization of Social Security in Sweden in 2000
— 456 funds, 1 default fund (chosen by government)
— Year 2000:
∗ Choice of default is discouraged with massive marketing campaign.
∗ Among new participants, 43.3 percent chooses default
— Year 2003:
∗ End of marketing campaign.
∗ Among new participants, 91.6 percent chooses default
— Side point for us (but key point in paper): Portfolio actively chosen inyear 2000 does much worse than default
9 Next Lecture
• More defaults effects in other settings
• Interpretation using present-biased preferences
• Consumption Choices
— Investment Goods
— Leisure Goods
• Problem Set 1 is due next week